Study On The Volatile Flavor And Adsorption In Subcutaneous Fat Of Three Chinese Dry-cured Ham

Dry-cured ham is a high-quality traditional meat product.It has a long history and good sensory characteristics.It is popular with the majority of people.Fat plays an important role in the formation and maintenance of dry cured ham volatile flavor.However,studies on the contribution of fat to ham flavor are unclear.In the present study,solid phase microextraction and gas chromatography-mass spectrometry technologies are used to study the comparison of the fatty acids and volatile compounds in subcutaneous fat and intramuscular fat of dry-cured ham and subcutaneous fat from different places of origin(Jinhua,Xuanwei,Rugao)and different processing time(one-year,two-year,three-year).On this basis,the effects of temperature(4?,25?),volatile compounds(5 kinds)and concentration(3 different concentrations)on the binding ability of raw pork fat to volatile compounds were investigated.This work lays the foundation for a theoretical basis for the mechanism of the binding ability of ham fat to volatile compounds.1.Comparison of Volatile compounds of Subcutaneous Fat and Intramuscular Fat in Dry-cured HamThis chapter analyzed the composition and source of volatile compounds from subcutaneous fat and instramuscular fat in dry-cured ham.The volatile compounds of subcutaneous fat and intramuscular fat in dry-cured ham were extracted by solid phase microextraction,and then were identified by gas chromatography-mass spectrometer.The fatty acids of both fats were further evaluated by gas chromatograph.Finally,the relative odor activity value(ROAV)was employed to identify their contributions to the ham falvor.Sixty and fifty-one volatile compounds were detected in dry-cured ham from subcutaneous fat and intramuscular fat,including 14 and 9 aldehydes,7 and 4 ketones,and 11 and 6 alcohols,1 and 2 aromatic hydrocarbons,8 and 8 esters,3 and 0 furans,8 and 7 acids,1 and 4 hydrocarbons,7 and 11 other species,respectively.A total of 21 fatty acids were detected in the two fats.Six volatile compounds had a great contribution for the flavor of the ham by calculating the ROAV values.During dry-cured ham processing,the differences of lipolysis and oxidation from intramuscular and subcutaneous fat resulted in differences of fatty acids and volatile compounds.2.Volatile Compounds in Subcutaneous Fat of Three Kinds of Traditional Chinese Dry-cured HamsTo identify the active volatile compounds and analyze the contribution of active volatile compounds to the overall flavor of three dry-cured ham subcutaneous fat,the subcutaneous fat was sampled from Jinhua,Rugao and Xuanwei hams for analysis of electronic nose and gas chromatography-mass spectrometry.The results showed that the electronic nose data of subcutaneous fat was identified and classified by aroma fingerprint.Sixty-two kinds of volatile compounds were detected.Fifteen volatile compounds 3-methylbutanal,hexanal,heptanal,octyl aldehyde,(E)-2-heptenal,nonanal,(Z)-2-octenal,2-nonenal,6-nonenal,(Z,Z)2,4-decadienal,1-octen-3-one,1-octen-3-ol,ethyl 2-methylbutyrate,2-n-pentylfuran and 2-ethylfuran selected by relative odor activity value contribute to the overall flavor of subcutaneous fat Therefore,the principal component analysis can distinguish the volatile flavor of subcutaneous fat of three kinds of dry-cured hams.3.Effects of Temperature and Concentrations on the binding ability of Fat to volatile compoundsIn order to explore the precise relationship between fat and volatile compounds,the subcutaneous fat of the fresh pig's hind legs was used as the experimental material,and the concentrations of volatile compounds and the adsorption temperature(4?,25?)were investigated.Volatile compounds were analysised by solid phase microextraction and gas chromatography-mass spectrometry.The temperature and functional groups of volatile compounds have a significant effect on the interactions between the fat and volatile compounds.The binding ability of fats to the 3-methylbutanal,1-octen-3-ol,1-octen-3-one,ethyl acetate,and hexanal is affected by the composition of fat,the properties and concentration of volatile compounds.